Sheep Veterinary Society (SVS) and Sheep Antibiotic Guardian Group (SAGG) advice for when an enzootic abortion (EAE) vaccine is unavailable

Both Sheep Veterinary Society (SVS) and Sheep Antibiotic Guardian Group (SAGG) are disappointed by the lack of enzootic abortion (EAE) vaccine this tupping season and we are aware that this will have a significant impact on sheep farmers and their flocks that currently rely on effective vaccination to control disease.

This press release aims to offer a measured response to support vets and farmers who will need to make difficult decisions for their flocks.

Much of our previous advice has not changed:

1. When faced with an aborting ewe, it is important that the ewe is isolated from the rest of the flock and that samples are taken to diagnose which abortion agent is responsible.
2. It is not appropriate to use routine prophylactic antibiotics to control abortion – the use of antibiotics in late pregnancy is only acceptable to protect other ewes in the group in face of an outbreak or in a group of ewes following a confirmed laboratory EAE diagnosis in the immediately preceding year.

For flocks that have previously regularly vaccinated against EAE, there will this year be a small cohort of unvaccinated replacement ewes but the risk to them is low if the remainder of the flock is protected.  They should be marked and vaccinated next year when they are not pregnant.

For flocks that are at high risk of disease (perhaps due to current or recent EAE abortion outbreak or following the introduction of EAE-shedding ewes into an unvaccinated flock) then there are a couple of options:

1. There is an inactivated vaccine (Inmeva; Hipra) which may be appropriate to use (note that two doses are necessary with the first dose given at least 5 weeks before mating and the second dose given 3 weeks after the first; a further booster is required within a year; this vaccine can be safely given during pregnancy with efficacy demonstrated in the mid trimester, but its use is not recommended in the final month of pregnancy).
2. Unvaccinated ewes at high risk of disease (confirmed by laboratory diagnosis) may be given a single injection of oxytetracycline (at 20mg/kg) between day 91 and day 126 of pregnancy. For groups with lambing spread over a four to five week period, this means injecting them exactly three weeks before the first ewe is due to lamb.

It is not appropriate for any flock to be given routine prophylactic antibiotic without a confirmed laboratory diagnosis of EAE in the current or previous lambing season.  Even in this circumstance, it is appropriate for the vet to undertake separate risk assessments for different cohorts of ewes.

Further information about the Inmeva vaccine is available from representatives of Hipra UK & Ireland Ltd.   Vets can contact their MSD Animal Health to access an information sheet with advice for the control of EAE in the situation of limited or unavailable EAE vaccine.

Editors Notes

The Sheep Veterinary Society (SVS) promotes sheep health and welfare through scientific meetings, workshops and training sessions and representation on the British Veterinary Association Council and specialist Committees. The Society was formed in 1967 and the Society’s five hundred members are drawn from all sectors of the sheep industry. Most members are veterinary surgeons but a quarter of the membership are advisers, researchers, farmers and shepherds.

Biosecurity and Disease management are the essential drivers for economic sheep farming, and this remains at the forefront of the Sheep Veterinary Society’s agenda and we will continue to move this forward with the conversations between local veterinary surgeons and their sheep farmer clients being our principal focus.

The Sheep Antibiotic Guardian Group (SAGG) is a voluntary group of cross sector organisations. It is responsible for co-ordinating the activity around antibiotic use in the sheep sector and to report progress on the antibiotic reduction targets on behalf of the sheep industry to the Responsible Use of Medicines in Agriculture (RUMA) Alliance. Outputs of this group are available on the RUMA website: ruma.org.uk

SAGG is chaired by Fiona Lovatt who reports on behalf of the group into the RUMA Targets Task Force. The group secretariat is provided by the Veterinary Medicine Directorate (VMD) and membership includes: National Sheep Association (NSA), Sheep Veterinary Society (SVS), National Farmers Union (NFU), Agriculture & Horticulture Development Board (AHDB), Quality Meat Scotland (QMS), Hybu Cig Cymru – Meat Promotion Wales (HCC), Red Tractor, Farm Assured Welsh Livestock and Responsible Use of Medicines in Agriculture Alliance (RUMA).

For further information contact:

Joe Henry, President, Sheep Veterinary Society – secretariat@sheepvetsoc.org.uk

Fiona Lovatt, Chair, Sheep Antibiotic Guardian Group – fiona@flockhealth.co.uk